Rippling, a leading workforce management platform, optimized their CI/CD pipelines by integrating Buildkite with AWS Spot Instances, achieving significant infrastructure cost reductions while maintaining performance and reliability. Facing challenges of scaling delivery speed, quality, and cost due to rapid growth, Rippling initially encountered issues with Spot Instance outages and interruptions but overcame these by developing services to switch to On-Demand Instances when necessary and broadening their Spot availability pool. Their strategic planning and iterative optimization resulted in a 60% reduction in EC2 compute costs and a 50% reduction in total cloud costs, while keeping developers satisfied with fast builds. By investing in monitoring and adapting their pipeline for Spot Instance interruptions, Rippling future-proofed their operations, ensuring further savings as they continue to expand. This approach demonstrates the effectiveness of creative problem-solving and innovative use of technologies like AWS Spot Instances, facilitated by the flexibility of Buildkite, to enhance cost-efficiency and scalability in CI/CD processes.